1. Field of the Invention
This invention relates to a mechanical apparatus having movable contacts such as information apparatus such as a magnetic disk device, a business machine, a personal or domestic apparatus or the like and a method of storing such mechanical apparatus. More particularly to prevention of a so-called conglutination phenomenon a phenomenon of an increase in operation resistance at movable contacts which may occur when such apparatus is left in an inoperative condition and so forth.
2. Description of the Prior Art
Description is first given of present situations of the prior art of a magnetic disk device which is used as an external storage device for a computer or a business machine and is one of representative technical apparatus to which the present invention can be applied. Conventionally, the record density of a magnetic disk serving as a storage medium increases as the gap between such magnetic disk and a magnetic head for recording and reproducing information on and from such magnetic disk decreases. Therefore, in recent years, magnetic disk devices commonly employ a so-called floating head system wherein a magnetic head and a surface of a magnetic disk are separated from each other by a very thin air layer.
By the way, in recent years, in order to achieve a further increase of the record density, a so-called contact start stop system (hereinafter referred to as CSS system) is adopted wherein surfaces of a magnetic head and a magnetic disk are mirror finished while the load to urge the magnetic head toward the surface of the magnetic disk against the dynamic lift of an air layer is set to a comparatively high value so as to further decrease the gap between the magnetic head and the magnetic disk such that, when rotation of the magnetic disk is stopped, the magnetic disk and the magnetic head are put into a mutually touching condition.
Meanwhile, a lubricant is commonly applied to a surface of a magnetic disk in order to decrease the sliding friction or resistance between the magnetic disk and a magnetic head and to prevent abrasion of them.
With such CSS system, however, since a magnetic head contacts at a location of a mirror finished surface of a magnetic disk in a stopping condition, an adhesive phenomenon or so-called ringing occurs between the magnetic head and the magnetic disk. Such adhesive phenomenon is promoted where lubricant applied to the surface of the magnetic disk accumulates at contacts between the magnetic disk and the magnetic head, and there is a problem that, where they are left in the condition for a long period of time, the sliding friction between the magnetic disk and the magnetic head increases so much that starting of rotation of the magnetic disk may be difficult or the magnetic disk and/or the magnetic head may be damaged.
Such technique as disclosed, for example, in Japanese Patent Laid-Open No. 63-9089 is conventionally known as a countermeasure for the problem.
In particular, upon starting of rotation of a magnetic disk from a stationary condition, a carriage arm on which a magnetic head is carried is swung to cancel a possible adhering condition between the magnetic head and the magnetic disk to prevent such problem as described above.
The technique described above, however, pays no attention to progress of an adhesive phenomenon during a disconnecting term in a condition in which no power source is connected to a magnetic disk device, such as upon packing, during keeping or storage or during transportation. Accordingly, there is a problem that a possible increase of the sliding friction between a magnetic disk and a magnetic head during such a disconnecting term cannot be prevented.
The problem of such increase of the sliding friction at movable contacts is likely to be caused by disconnection for a long period of time even with regard to movable contacts of a personal device such as a camera or a watch or a domestic electric device. In addition to the adhesive phenomenon described above, rust or mildew makes another problem.